Physics
I think of myself as non-violent, a purple guy in the blue state of Massachusetts.When it comes to proposals in science though, I go for head shots. Nature doesn’t care if we keep repackaging bullshit. A well-fed bull does not run out of bullshit.
To stop a science zombie, a bullet to the brain is all that might stop it. I know from experience that the easiest person to fool is myself. I am on the lookout for bullets for subjects I speculate on.
I am a poor student of my own personal history, so this is only an approximate timeline. In 1997, I got interested in quaternions based on a contest…
I feel quite grateful to the DZERO collaboration for publishing today in the Cornell arxiv the preprint of their search for neutral MSSM Higgs bosons in the tau-pair decay mode. Not more than 12 hours ago in fact I had been looking for a suitable figure which could summarize the status of searches for those particles, to help a student who is about to graduate; but had not found anything satisfactory.
Now DZERO throws no less than 7.3 inverse femtobarns of collisions at this important search. I guess this is the swan song for this particular analysis at the Tevatron, because the LHC…
vongehr |
This recent Nature article makes people jump up and down in classical, non-quantum jumps as we speak: “Experimental non-classicality of an indivisible quantum system”.
There are plenty of misleading news articles already, including here on Science2.0, about that this experiment is disproving classicality without even needing “spooky action at a distance” or entanglement. The message one often takes away is therefore that this new experiment may be the best proof yet, the most convenient disprove of hidden variables.
Alas, it is not so. In fact, it is puzzling why this made it into Nature at…
Hank |
Quantum entanglement was strange when it was conceptualized. It violated Einstein's famous speed limit in his Theory of Relativity and he called it spukhafte Fernwirkung - “spooky action at a distance” and sought to note the flaws in Heisenberg's uncertainty principle and the Copenhagen interpretation. The result was the Einstein–Podolsky–Rosen paradox.
Since that Golden Age of theoretical physics thought experiments, much has changed. In 1964, John Stewart Bell showed how the principle of locality, one of the key assumptions in the EPR paradox, conflicted with…
ujm |
Continued from the last post.
Discounting the Bohmian song and dance, we are led to conclude that each electron does in some sense pass through both slits. But in what sense? Saying that an electron went through both slits cannot be equivalent to saying that the electron went through L and that it went through R, for to ascertain the truth of a conjunction we must individually ascertain the truths of its components, and we never find that an electron launched at G and detected at D has taken the left slit and that it has taken the right slit.
Nor can saying that an electron went through both…
A paper describing the first evidence of top pair production in association with a energetic photon has just appeared on the Cornell Arxiv. This search has been performed by the CDF collaboration in a sample of 6 inverse femtobarns of proton-antiproton collisions.
There is nothing strange or particular about the fact that any hard production process at a hadron collider can produce, in addition with a massive state such as a top pair, additional energetic photons. That is because any charged particle involved in the process will have a small but finite chance of radiating electromagnetic…
A great title is key to getting lots of views. For my blogs, ones with the fewest views include “Snarky Puzzle Answers”, and “Snarky Puzzle Answers 2”. Do I have high expectations for SPA 3, Revenge of the Nerds? Nope, I expect the community to be consistent. This is an observation, not a complaint, honest.
What is exciting to me is that I am asking questions and developing answers. I want to emphasize the plural. This is not a one trick pony (quaternions can do 3D rotations and nothing else of interest). Many different topics are being raised and looked at from odd angles. I didn’t have a…
vongehr |
The Quantum Randi Challenge (QRC), first introduced here, exists in order to stop the spread of pseudo-science by simply teaching quantum mechanics. Here is the official version of the challenge (also published here and partially in Annals of Physics 339: 81-88). [We are still looking for people who can help to turn it into a multiplayer internet app.*]
What is a “Randi-type” challenge?
A Randi-type challenge is one modeled after the James Randi Challenge. James offers USD 1000000 to anyone that can demonstrate paranormal abilities under laboratory conditions. A Randi-type challenge has the…
ujm |
According to Feynman, the 2-slit experiment with electrons "has in it the heart of quantum mechanics" and "is impossible, absolutely impossible, to explain in any classical way". To begin with, it may not be amiss to inform the never-ending discussion of this experiment with a knowledge of the rules that go into calculating the predicted and observed interference pattern.
The mathematical formalism of quantum mechanics can be built up on the basis of the following rules. Suppose that you want to calculate the probability of a particular outcome of a measurement M2, given the outcome of am…
The ATLAS Collaboration, one of the two high-energy physics experiments at the CERN Large Hadron Collider, has just produced updated results of their ongoing search for new heavy particles decaying into lepton pairs. They are now using up to 236 inverse picobarns of 7 TeV collisions, which is seven times more data than previous searches based on 2010 datasets. A seven-fold increase in data size grants a significant increase in sensitivity, so it is worth taking a look at what they see.
The technical way to call the sought particles is "Z' resonances", since they can be thought of as heavier…